Re: metadata plugins (was Re: the " 'official' point of view" expressed by kernelnewbies.org regarding reiser4 inclusion)

Nikita Danilov
2006-07-29T12:33:51Z

Hans Reiser writes:
> David Masover wrote:
>
> >
> > If indeed it can be changed easily at all. I think the burden is on
> > you to prove that you can change it to be more generic, rather than
> > saying "Well, we could do it later, if people want us to..."
>
> None of the filesystems other than reiser4 have any interest in using
> plugins, and this whole argument over how it should be in VFS is
> nonsensical because nobody but us has any interest in using the
> functionality. The burden is on the generic code authors to prove that
> they will ever ever do anything at all besides complain. Frankly, I
> don't think they will. I think they will never produce one line of code.
>
> Please cite one ext3 developer who is signed up to implement ext3 using
> plugins if they are supported by VFS.

In fact, they all do:

struct inode_operations ext2_file_inode_operations;
struct inode_operations ext2_dir_inode_operations;
struct inode_operations ext2_special_inode_operations;
struct inode_operations ext2_symlink_inode_operations;
struct inode_operations ext2_fast_symlink_inode_operations;

As you see, ext2 code already has multiple file "plugins", with
persistent "plugin id" (stored in i_mode field of on-disk struct
ext2_inode).

>
> Hans
>

Nikita.